Is this a good raidz1 to raidz2 migration plan?

[Last Mile]

A year ago I was just experimenting with FreeNAS with a spare desktop server from work. Following several of the online how to guides, I turned up a 3 x 2TB RaidZ1. Now, I see RaidZ1 isn't recommended, but is much better than buying an external drive from Costco.

My Dell T3400 motherboard has 5 SATA connectors, one for the DVD, three for the RaidZ1 and one spare.

My plan is back everything up onto a new 6TB drive and turn the 3 x 2TB RaidZ1 into a 4 x 2TB RaidZ2. (Or, 3 x 2TB plus 1 x 6TB)

I'd rather not use an external USB drive to back everything up, so I came up with this plan.
1. Disconnect the DVD and use the SATA port for a new 6TB drive.
2. Add a new 2TB (or 6TB) drive to the existing RaidZ1 group to be migrated to RaidZ2.
3. Use Storage -> Volume Manager to create a new data set called set2
4. Use Storage -> Volume Manager -> Import Volume and import all of set1 into set2
5. Verify data in set2, then Detach volume set1
6. Power down and connect the 4th drive in the old set1
7. Power up, destroy the set1 dataset
8. Create a new dataset set1 with 4 drives in RaidZ2
9. Use Storage -> Volume Manager -> Import Volume and import all of set2 (single drive) into set1 (new RaidZ2)

Is this doable? Is there a better way? I'm open to suggestions.

Thanks in advance.

 

[BigDave]

My plan is back everything up onto a new 6TB drive and turn the 3 x 2TB RaidZ1 into a 4 x 2TB RaidZ2. (Or, 3 x 2TB plus 1 x 6TB)

I will suggest you use the new 6TB drive only after it's tested (burned in) with badblocks/SMART tests.
Use the SATA port from the removal of the Optical Drive and add the 6TB drive as a new pool
(Not added to the existing pool)

If your existing RAIDz1 pool has not been scrubbed in a while (14 days or longer),
get this done before copying anything over.

Copy your files from old RAIDz1 pool to the single drive (6TB) pool.

VERIFY the files are whole/complete before destroying the old pool.

Burn in any new drives that will be used to construct the new pool.

Destroy the old pool and rebuild the new pool as desired.

What you do with the 6TB drive from here is optional, I used mine
in my Windows desk top and keep my files there. For me, FreeNAS
is a backup and is rarely accessed.

 

[Last Mile]

BigDave,
Thanks for the reply. You added steps of pre-testing the new drives was already in my overall plan. I figure it will take a couple of days to do so.

Is there an easy way to copy the files from one volume (same as pool?) to the other? I was thinking of using Import Volume from the gui. People have said it can be done over ssh, but not have the session interrupted. Why can't I use terminal connected to the server, should be the same.

After all this is done I would have a 4 drive RaidZ2. The drive in the optical drive bay would then be used to replace one of the existing 2TB drives, so I can put the DVD back in.

Again, many thanks for your help.

 

[Last Mile]

On last question. Even if I don't use an external USB drive and use an internal drive instead, is it still necessary to create a duplicate system dataset pool through System -> System Dataset Pool?

It's my understanding the System Dataset Pool holds how the Raid pool contains and how it is setup with drives, jails, etc.

Sorry for asking so many questions, I just want to be sure before I do something dumb or I missed something in the documentation.

Thanks

 

[BigDave]

It's my understanding the System Dataset Pool holds how the Raid pool contains and how it is setup with drives, jails, etc.

The System Dataset is a group of files that contains your configuration, how your pool is set up, jails, etc.
The dataset is not a "pool".
You can move the dataset (drop down in the GUI) to your boot device or keep it on your drives that make up your pool.
At this point in time, I would recommend familiarizing yourself with the manual BEFORE doing making changes of any kind.
I don't use jails of any kind so someone else will have to help with getting those things squared away before you rebuild the pool.

 

[BigDave]

After all this is done I would have a 4 drive RaidZ2. The drive in the optical drive bay would then be used to replace one of the existing 2TB drives, so I can put the DVD back in.

I'm confused as to why you would want to replace one of the 2TB drives with the 6TB one, right after rebuilding the volume?
Maybe I haven't had enough coffee yet this morning...

 

[gpsguy]

When I read it this morning, I wondered why the OP wanted to the the DVD back in.

I'm confused as to why you would want to replace one of the 2TB drives with the 6TB one, right after rebuilding the volume?

 

[Last Mile]

I'm confused as to why you would want to replace one of the 2TB drives with the 6TB one, right after rebuilding the volume?
Maybe I haven't had enough coffee yet this morning...

The migration from RaidZ1 to RaidZ2 will yield a 3 x 2TB + 1 x 6TB config. I can then replace one of the 2TB with the 6TB that previously held my data, give me a 2 x 2TB + 2 x 6TB. As my budget allows I'll replace remaining 2TB drives and I'll have a 4 x 6TB and three freed up 2TB drives for other projects.